임명섭 교수

This paper presents a design methodology and analysis for a 4-kW 150-krpm ultra-high-speed surface-mounted permanent-magnet synchronous motor (SPMSM) to electrically assist a turbocharger. The proposed design methodology is aimed at achieving a required torque and speed. In addition, this study seeks a fast-speed response as a design objective to eliminate turbo lag more effectively. First, an existing prototype that does not meet the target performance is presented. The loss for the prototype,

This paper proposes the design process of a 2.62-kW 150-krpm high-speed surface-mounted permanent-magnet synchronous motor. To meet the required specifications, the numbers of poles and slots were determined by considering the maximum speed and the rotary stability affected by the vibration of the rotor. In addition, this paper describes not only the appropriate material selection method but also the appropriate geometry design method based on analytic approaches. Furthermore, to precisely evalu

In this paper, a design method for a wound field synchronous motor (WFSM) employing the dual stator winding and the winding connection change circuit is proposed. Through the design method, the WFSM can be operated as two different modes, and each mode is determined by the connection between the stator windings U, V, W and X, Y, Z. By applying the proposed method to the conventional WFSM, the operation mode of the motor is changed at a certain speed. The speed for the mode change is determined t

This paper investigates the influence of the geometry design parameters of an interior permanent magnet synchronous motor with concentrated winding on the saliency-based sensorless drive feasibility. To evaluate the sensorless controllability of the motors, two different methods to estimate the rotor position error are proposed. By using the methods, the geometry design parameters in the stator are analyzed to figure out which ones have a positive effect on the sensorless drive. The analysis res

This study investigates the influence of the stator configuration of low‐speed sensorless‐controlled interior permanent magnet synchronous motors (IPMSMs) with concentrated winding on the sensorless drive feasibility and iron loss. To evaluate the sensorless controllability of the motors, a mathematical and simulation process of estimating the rotor position error is proposed. In addition, the harmonic iron loss under a load condition is analysed via two‐dimensional non‐linear finite element ana

The magnetic properties of a motor core deteriorate during the manufacturing process due to mechanical stresses in the materials. It is particularly hard to predict the characteristics of the slinky-laminated electrical machines, because stresses and strains occur simultaneously in the core. To examine the B-H curve and the iron loss of a core affected by the manufacturing process, a slinky-laminated surface-mounted permanent magnet synchronous motor (SPMSM) was proposed as an analysis model. Th

In this study we developed a brushless DC (BLDC) slotless motor with toroidal winding. The proposed toroidal winding is a method of winding a coil around a ring-type stator yoke in the circumferential direction. As there is no need for a slot or tooth structure, it can be designed with a slotless motor structure that is advantageous for vibration and noise. The basic principle of operation and motor characteristics of a slotless motor with toroidal winding were explained using an analytical meth

The B–H curve and iron loss of electrical steel sheets are essential data for predicting the performance of electric motors. The Epstein frame test is widely adopted to acquire these magnetic properties. However, for rotating electric machines with relatively small geometry, the ring specimen test is preferred because of its simplicity and geometric similarity. This study deals with the experimental verification of the ring specimen test. The B–H curve and iron loss of non‐oriented electrical st

Static eccentricity (SE) is frequently generated by manufacturing processes. As the nonuniformity of the air-gap length is caused by the SE, the torque ripple and cogging torque increase in the motor. This study analyzes the distorted back electromotive force (EMF) and cogging torque due to SE. Further, a motor design considering SE is performed for stable back EMF and low cogging torque. First, the SE was diagnosed and analyzed using the back EMF and cogging torque measured from the test result